internecine
1. [ adjective ] (of conflict) within a group or organization
Examples:

"an internecine feud among proxy holders"

Related terms: internal
2. [ adjective ] characterized by bloodshed and carnage for both sides
Synonyms: mutually_ruinous
Examples:

"internecine war"

Related terms: bloody
Similar spelling:   internee
  internet
  intertwine
  interaction
  intervening
  intertwined
  interactive
  internal
  internist
  internode
  interdiction
  intercede
  interference
  interpretive
  interfere
  intersection
  interspecies
  interjection
  interface
  intervene
  interlace
  interlinking
  intercept
  internalise
  internalize
  internet_site
  interbreeding
  interspecific
  interactional
  internment
  internship
  interlaced
  internally
  interphone
  interbrain
  interferon
  innate_reflex
  intercessor
  interesting
  interconnected
  interceptor
  interfering
  intermingle
  interlacing
  interiorize
  interiorise
  internuncio
  interbreed
  interior
  interconnect
  intercom
  interviewer
  intercession
  interlocking
  interception
  internal_ear
  interpreted
  interpreter
  interpreting
  intersecting
  intersperse
  interact
  interviewee
  interleukin
  interchange
  intercellular
  intercalate
  interbred
  intercourse
  interlock
  interestingly
  interview
  intervention
  intersect
  interpret
  interpose
  Internationale
  international
  internal_rhyme
  internal_drive
  internal_angle
  interminable
  interment
  interlude
  interlope
  interlink
  interlinear
  interlineal
  interlard
  interject
  interdict
  in_theory